The following partial words can be completed according to a certain pattern. What is the pattern and what are the new words?

1. SEN
2. SIM
3. DEF
4. VIR
5. FUT

Answer:

The letters ILE, added at the end, will complete each partial word:

1. SENILE
2. SIMILE
3. DEFILE
4. VIRILE
5. FUTILE